lets think about this logistically. Google is a great many things, but they are not a retail giant. Each person that orders a phone via google, need to have information entered, labels created, boxes to stuff and all that stuff.
Verizon already has your information. they already have stores/warehouses and all the stuff needed to process orders for many location and ship simultaneously. To google you are a single user end customer. Verizon is not those things.
BTW why do you think Google had more then one option for buying thru them. Probably to split orders naturally amoung staff without having to change supply channels.
Is this right, no. Will google get better. They better now that they have to kick the dirt off there new phone manufacturing company.